Recent publications in Australia focus on "number sense" as an important component of mathematics instruction. The current study attempted to tap into local expert knowledge in the area of early mathematics in an effort to establish a consensus on which skills reflect the number sense typically acquired by school entry. A modified Delphi procedure was employed whereby participants were asked to indicate their level of agreement with a variety of skills as indicators of number sense in young children. The study raised questions about the efficacy of this type of participatory research when used in relation to an ill-defined construct. It also revealed a lack of consensus among the group of academics who agreed to participate in the study.